Such lubrication systems are also known as central lubrication systems and serve to supply grease to a plurality of lubrication locations on the vehicle, so that even in driving operation a deficiency of grease with concomitant rapid wearing of moving parts is prevented. Typical lubrication locations are various areas of the fifth wheel or the steering knuckle pins of the vehicle.
From the prior art there is known, for example, EP 1 209 038 A1, which likewise discloses a lubricant reservoir and a pump, which delivers the lubricant to a distributor and to at least one direct line running directly to the lubrication location. In a lateral region of the lower pump segment is arranged a control unit, with which it is possible to set certain control parameters, such as the cycle time and the lubrication time. Alternatively, it is proposed to connect the lubricant pump or central lubrication system by an interface to the central onboard computer of the vehicle, which makes the control and monitoring, as well as the operation of the central lubrication system much more comfortable. A separate control unit is not needed with this configuration.
Thus, in the above-described central lubrication system, the higher-level electronics of the vehicle located in the on-board computer activates the lubrication system and carries out diagnostic functions for trouble-shooting. The higher-level electronics of the vehicle is usually also able to activate the central lubrication system with different lubrication programs, so that the supply of lubricant is satisfied also for various operating conditions of the vehicle. In long-haul operation, of course, less grease is required for the axles and the fifth wheel than when the vehicle is operated in the construction site duty.
The drawback of these now widely used lubrication systems is that the customer must order a vehicle with a higher-level vehicle electronics in order to take advantage of the above-described ease of operation. The extensive higher-level electronics, however, is usually not needed at all by the customer, except for operating the central lubrication system. Furthermore, the selection of the lubrication program must be done by a service shop with an appropriate diagnostic and operating tool.
A generic prior art is constituted by WO 2006/084752 A1, with a lubrication system for the exclusive supplying of grease to the fifth wheel. The components of this known lubrication system, besides the control unit, are to be situated in modular fashion in spatial proximity to the fifth wheel. Supplying of other lubrication locations is not contemplated.
U.S. Pat. No. 5,417,308 A proposes supplying lubricant exclusively to the fifth wheel by a lubrication system operated remotely from the driver's cabin. However, ejection of lubricant occurs only by a manual activation of an operating button by the driver. An automatic lubrication operation with several lubrication programs is not provided.